Cross-Chain Interoperability
Harmony’s bridges can connect any Proof-of-Work and Proof-of-Stake chains. Our FlyClient architecture is fully trustless and highly gas-efficient. Currently, our bridges for Ethereum and Binance Smart Chain secure tens of millions cross-chain assets.
Developers simply change Chain ID and enjoy faster EVM executions identical at the bytecode level. They can use their familiar and standard Web3 tooling to easily migrate to Harmony.
What about users? They can continue to use MetaMask or Ledger — but now pay minimal fees. Any Ethereum wallets or portals can work on Harmony without code changes or new installs — we are fully compatible for both transaction messages and execution environments.
Protocol Strengths
1. Secure, Random State Sharding
Harmony has transcended the blockchain trilemma by bringing the best research to production. Sharding is proven to scaleblockchains without compromising securityand decentralization.We divide not only our network nodes but also the blockchain states into shards, scaling linearly in all three aspects of machines, transactions and storage.To prevent single shard attacks, we must have a sufficiently large number of nodes per shard and cryptographic randomness to re-shard regularly. Each shard has 250 nodes for strong security guarantee against Byzantine behaviors. We use Verifiable Delay Function (VDF) for unbiasable and unpredictable shard membership.
2. Fast Consensus w/ Instant Finality
Harmony has innovated on the battle-tested Practical Byzantine Fault Tolerance (PBFT) for fast consensus of block transactions. Our Fast BFT (FBFT) leads to low transaction fees and 1-block-time finality in Harmony Mainnet.We use Boneh–Lynn–Shacham (BLS) constant-sized signatures to commit blocks in a single round of consensus messages. We achieve 2-second block time with view changes in production against adversarial or unavailable leaders.Harmony Mainnet was launched in June 2019. Our network has produced 30M+ blocks with 450k+ transactions in publicly traded, native ONE tokens.
3. Effective PoS & Token Economics
Harmony has designed a novel Proof-of-Stake (PoS) mechanism for network security and economics. Our Effective Proof-of-Stake (EPoS) reduces centralization and distributes rewards fairlyto thousands of validators.Our staking mechanism supports delegation and reward compounding. To support 100% uptime but fully open participation, EPoS slashes validators who double-sign and it penalizes elected but unavailable nodes.Harmony Economics Model caps the annual issuance at 441 million tokens (about 3% rate in long term). Our model gives validators a simple and predictable return. All transaction fees are burnt to offset the issuance, naturally leading to zero inflationwhen our network usage becomes high.
Messari's Report on ONE
Harmony Developers
Harmony is your open platform for assets, collectibles, identity, governance. We are an open and fast blockchain. Our mainnet runs Ethereum applications with 2-second transaction finality and 1000 times lower fees. Harmony's secure bridges offer cross-chain asset transfers with Ethereum, Binance and other chains.
dev.harmony.one
Consensus
The consensus algorithm is a key component of any blockchain. It determines the security and performance of a blockchain and is often referred to as the "engine" of a blockchain. Harmony's consensus algorithm is called Fast Byzantine Fault Tolerance (FBFT) , which is an innovative upgrade on the famous PBFT algorithm.
docs.harmony.one
On-Chain Staking & Delegation
Name | Assign | Status | Next Milestone Date | Release Date |
|---|---|---|---|---|
RPC optimization - getLogs |  Jenya Piskunov Jack Chan | Live on Devnet | 2022/02/14 | 2022 Q2 |
Decentralized Nodes |  Leo ChenJack Chan/w=48,quality=90,fit=scale-down){kind=small} Nita Neou (Soph) | Execution Started | 2022/02/14 | 2022 Q3 |
Validator DAO HIP proposals |  Yuriy M | Objective Defined | 2022/03/04 | 2022 Q2 |
Decentralized RPC | Nita Neou (Soph)Leo ChenJack Chan | Execution Started | 2022/03/31 | 2022 Q3 |
Elastic RPC | Leo Chen | Live on Testnet | 2022/06/10 | 2022 Q2 |
Streaming Sync & Fast Sync |  Jacky Wang Rongjian Lan | Live on Testnet | 2022/06/20 | 2022 Q3 |
Decentralized Ops | Jack ChanLeo ChenRongjian Lan | Execution Started | 2022/06/30 | 2022 Q4 |
 |  Ganesha UpadhyayaJenya Piskunov | Live on Devnet | 2022/06/30 | 2022 Q3 |
Cross-Chain API |  Boris PolaniaGanesha Upadhyaya | Live on Testnet | 2022/07/25 | 2022 Q3 |
 | Ganesha Upadhyaya | Objective Defined | 2022/07/25 | 2022 Q3 |
 | Ganesha Upadhyaya | Objective Defined | 2022/08/29 | 2022 Q4 |
Cross-Shard Transaction | Rongjian Lan | Execution Started | 2022/10/31 | 2022 Q3 |
1-Second Finality | Rongjian LanJacky Wang | Execution Started | 2022/12/31 | 2022 Q4 |
Secure Resharding | Rongjian Lan | Objective Defined | 2023/05/31 | 2023 Q1 |
Bring Research to Production
- Zeta Avarikioti – toward 1-second transaction finality: determine the optimal shard size against network security for our Proof-of-Stake network, compare to Mahdi Zamani's Rapidchain and Instachain;
- Ivan Homoliak & Andrianna Polydouri – toward authenticator-based wallets: client-side encryption security and performance, one-time-password (OTP) Merkle-tree generation and authenticator security.
- Dionysis Zindros (at decrypto) – toward logarithmic states: Flyclient/NiPoSPoS-based bridges vs ZK-rollups vs Interlay/XClaim's economics security, fast state sync for mining and resharding, keyless wallets with lattice-based witness encryption;
- Dimitris Karakostas – toward supporting 100k delegators: optimizations of Harmony's on-chain delegations and compounding rewards;
- Aaron Li – toward end-to-end formal verification: prove security of Harmony's authenticator-based wallets in Coq, smart contract audits on Horizon bridges for Ethereum and Bitcoin.
Projects in Need of Audits
https://github.com/harmony-one/horizon (main branch) commit: 88820b7ab6427c860cdb67e31d796d30c3940c5a Trustless Ethereum Bridge https://github.com/harmony-one/onebtc (main branch) commit: 9975700d9c5fdadbff2e7b10d857c615b66f5915 Bitcoin Bridge https://github.com/polymorpher/one-wallet/tree/master/code (main branch) https://github.com/polymorpher/one-wallet/tree/master/audits (prior audits) $20M Grants & Bounties on Wallets
harmony.one
Common Prefix - Harmony
Common Prefix is a team of scientists and engineers specializing in blockchains. We work from first principles, with an eye for rigor and formal cryptographic security proofs. We contribute as the advisory team for Harmony's underlying science.
www.commonprefix.com
www.commonprefix.com
www.commonprefix.com
Harmony Consensus - Roadmap (tentative)
Harmony Consensus - Roadmap (tentative) Auction mechanism P0: Designate desirable properties and study whether the current protocol lacks them (these properties are different in a blockchain setting VS a traditional auction mechanism) - January 2022 P0: Devise concrete attack parameters and des...
docs.google.com
zkDAO – Succinct, Private, Fair
Ethereum 3.0? Scaling Cryptography in Blockchain
Ethereum 3.0? Scaling Cryptography in Blockchain applications exchanges: deversifi, loopring, immutable-x, tornado, starkware stateless: flyclient, zksync, zk² rollup scale: rollups (uniswap, idex, 0x), vm, fraud proofs, reddit points compose: bridges, swaps, wraps, pegs, defi, on-demand liqu...
harmony.one
Sharding Consensus and Contracts
Harmony's latest technical architecture is now detailed in our new whitepaper and token economics in our staking design. Below are our notes on Omniledger, Rapidchain and Chainspace for sharding consensus and contracts. We're looking for hires (see our 3x3 interview questions on culture and values) and collaborators (wine and ramen)!
medium.com
Harmony - Open Consensus for 10B
Harmony is a fast and open blockchain for decentralized applications. Our mainnet supports state sharding with instant finality. Our staking mechanism reduces centralization while supporting delegation and slashing.
staking.harmony.one